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With the advent of antiretroviral therapies, persons living with HIV/AIDS (PLHIVs) are living longer but with increased impairment and care needs. The purpose of this study was to assess whether a vulnerable population of PLHIVs preferred informal versus professional care when unable to care for themselves, and individual and support network factors associated with preference for informal care. The findings have potential implications for facilitating the population's informal care at end of life. Data were from the BEACON study, which examined social factors associated with health outcomes among former or current drug-using PLHIVs in Baltimore, MD. Structural equation modeling was used to identify individual and support network characteristics associated with PLHIVs' preference for informal (family or friends) compared to professional care. The structural equation model indicated preference for informal care was associated with female sex, greater informal care receipt, reporting one's main partner (i.e., boy/girlfriend or spouse) as the primary source of informal care, and a support network comprised greater numbers of female kin and persons supportive of the participant's HIV treatment adherence. Not asking for needed help to avoid owing favors was associated with preferring professional care. Findings suggest that interventions to promote informal end of life care should bolster supportive others' resources and skills for care provision and treatment adherence support, and should address perceived norms of reciprocity. Such intervention will help ensure community caregiving in a population with high needs for long-term care.  相似文献   
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Microbubbles driven by ultrasound are capable of permeabilizing cell membranes and allowing biomarkers or therapeutics to exit from or enter cancer cells, respectively. Unfortunately, the relatively large size of microbubbles prevents extravasation. Lipid-based perfluorobutane microbubbles can be made seven-fold smaller by pressurization, creating 430-nm nanodroplets. The present study compares microbubbles and nanodroplets with respect to their ability to enhance miR-21 and mammaglobin mRNA release from cultured ZR-75-1 cells. Mammaglobin mRNA and miR-21 release increased with escalating concentrations of nanodroplets up to, respectively, 25- and 42-fold with 2% nanodroplets (v/v), compared with pre-ultrasound levels, whereas cell viability decreased to 62.4%. Sonication of ZR-75-1 cells incubated with microbubbles or nanodroplets caused relatively similar levels of cell death and miR-21 release, suggesting that nanodroplets are similar to microbubbles in enhancing cell permeability, but may be more advantageous because of their smaller size, which may allow extravasation through leaky tumor vasculature.  相似文献   
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Nodal is highly expressed in various human malignancies, thus supporting the rationale for exploring Nodal as a therapeutic target. Here, we describe the effects of a novel monoclonal antibody (mAb), 3D1, raised against human Nodal. In vitro treatment of C8161 human melanoma cells with 3D1 mAb shows reductions in anchorage-independent growth and vasculogenic network formation. 3D1 treated cells also show decreases of Nodal and downstream signaling molecules, P-Smad2 and P-ERK and of P-H3 and CyclinB1, with an increase in p27. Similar effects were previously reported in human breast cancer cells where Nodal expression was generally down-regulated; following 3D1 mAb treatment, both Nodal and P-H3 levels are reduced. Noteworthy is the reduced growth of human melanoma xenografts in Nude mice treated with 3D1 mAb, where immunostaining of representative tumor sections show diminished P-Smad2 expression. Similar effects both in vitro and in vivo were observed in 3D1 treated A375SM melanoma cells harboring the active BRAF(V600E) mutation compared to treatments with IgG control or a BRAF inhibitor, dabrafenib. Finally, we describe a 3D1-based ELISA for the detection of Nodal in serum samples from cancer patients. These data suggest the potential of 3D1 mAb for selecting and targeting Nodal expressing cancers.  相似文献   
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